Genetic theories have as much to do with culture as science

The overwhelming similarity of human DNA to that of the chimpanzee shows not that we are `mostly' chimp but how little we actually understand about DNA after all

By Jonathan Marks

Context reveals something at the low end of the scale as well. Two DNA sequences generated at random must be 25 percent identical, by virtue of the fact that DNA is a sequence of only four bases. Therefore, all multicellular life, having presumably developed from a single common ancestral form, must be over 25 percent identical in their DNA sequences.

In other words, a human and a carrot have much in common genetically, despite their being little similarity between them physically. Here the DNA comparison grossly overestimates the actual relationships between species. Genetic comparisons simply do not afford an "inner view" of the relationships between species, or an encapsulation of those relationships.

In other words, this apparent fact of nature -- the overwhelming genetic similarity of human and ape -- is a fact constructed from culture. That is not to say it is inaccurate or false; just that its meaning is far less obvious than it may appear superficially.

We make sense of the world, and of our place in it, culturally, and science provides more information for constructing that place. Our own application of that information to the puzzle of our existence is strongly influenced by our non-scientific ideas, our pervasive folk ideologies of heredity.

Jonathan Marks is a biological anthropologist at the University of North Carolina, Charlotte, and the author of What It Means To Be 98 percent Chimpanzee: Apes, People, and Their Genes. Copyright: Project Syndicate